644016732 has 48 divisors (see below), whose sum is σ = 1516244352. Its totient is φ = 212748480.

The previous prime is 644016697. The next prime is 644016733. The reversal of 644016732 is 237610446.

It is a happy number.

644016732 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 644016693 and 644016702.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644016733) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 878238 + ... + 878970.

It is an arithmetic number, because the mean of its divisors is an integer number (31588424).

Almost surely, 2^644016732 is an apocalyptic number.

It is an amenable number.

644016732 is an abundant number, since it is smaller than the sum of its proper divisors (872227620).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

644016732 is a wasteful number, since it uses less digits than its factorization.

644016732 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1298 (or 1296 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 33.

The square root of 644016732 is about 25377.4847453407. The cubic root of 644016732 is about 863.5729896558.

The spelling of 644016732 in words is "six hundred forty-four million, sixteen thousand, seven hundred thirty-two".